Skip to main content

CodeSOD: Back Up for a Moment

2 days 6 hours ago

James's team has a pretty complicated deployment process implemented as a series of bash scripts. The deployment is complicated, the scripts doing the deployment are complicated, and failures mid-deployment are common. That means they need to gracefully roll back, and they way they do that is by making backup copies of the modified files.

This is how they do that.

DATE=`date '+%Y%m%d'` BACKUPDIR=`dirname ${DESTINATION}`/backup if [ ! -d $BACKUPDIR ] then echo "Creating backup directory ..." mkdir -p $BACKUPDIR fi FILENAME=`basename ${DESTINATION}` BACKUPFILETYPE=${BACKUPDIR}/${FILENAME}.${DATE} BACKUPFILE=${BACKUPFILETYPE}-1 if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-2 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-3 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-4 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-5 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-6 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-7 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-8 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then BACKUPFILE=${BACKUPFILETYPE}-9 ; fi if [ -f ${BACKUPFILE} ] || [ -f ${BACKUPFILE}.gz ] ; then cat <<EOF You have already had 9 rates releases in one day. ${BACKUPFILE} already exists, do it manually !!! EOF exit 2 fi

Look, I know that loops in bash can be annoying, but they're not that annoying.

This code creates a backup directory (if it doesn't already exist), and then creates a file name for the file we're about to backup, in the form OriginalName.Ymd-n.gz. It tests to see if this file exists, and if it does, it increments n by one. It does this until either it finds a file name that doesn't exist, or it hits 9, at which point it gives you a delightfully passive aggressive message:

You have already had 9 rates releases in one day. ${BACKUPFILE} already exists, do it manually !!!

Yeah, do it manually. Now, admittedly, I don't think a lot of folks want to do more than 9 releases in a given day, but there's no reason why they couldn't just keep trying until they find a good filename. Or even better, require each release to have an identifier (like the commit or build number or whatever) and then use that for the filenames.

Of course, just fixing this copy doesn't address the real WTF, because we laid out the real WTF in the first paragraph: deployment is a series of complicated bash scripts doing complicated steps that can fail all the time. I've worked in places like that, and it's always a nightmare. There are better tools! Our very own Alex has his product, of course, but there are a million ways to get your builds repeatable and reliable that don't involve BuildMaster but also don't involve fragile scripts. Please, please use one of those.

[Advertisement] Plan Your .NET 9 Migration with Confidence
Your journey to .NET 9 is more than just one decision.Avoid migration migraines with the advice in this free guide. Download Free Guide Now!
Remy Porter

Iran seeks at least three cloud providers to power its government

2 days 8 hours ago
Despite loathing the USA, Iran wants providers who match NIST’s definition of cloud computing

The Information Technology Organization of Iran (ITOI), the government body that develops and implements IT services for the country, is looking for suppliers of cloud computing.…

Simon Sharwood